Sediment Resuspension and Hydrodynamics in Lake Okeechobee during the Late Summer

Abstract

In this study, in order to better understand the mechanisms affecting sediment resuspension, extensive data sets were collected in September and October of 2002 including wind velocity, wave, current velocity, water temperature, total suspended solid, suspended sediment concentration, and total phosphorus. Analyses of these data indicate that waves are the dominant factors in sediment resuspension while wind-induced currents are the primary forces to transport suspended sediments. Surface and bottom currents frequently flow in opposite directions, forming a stratified water column. A time lag exists between currents near lake bottom and wind forcing at the surface. The diurnal thermal stratification occurs in the deep region of the lake. A time lag is also found between suspended sediment concentration and wind speed. The study provides valuable storm-event data and mechanism analyses, which can improve our understanding of the lake circulation, wave dynamics, and their impact on sediment resuspension and vertical mixing in Lake Okeechobee. The data resulting from this study will be used to validate the Lake Okeechobee Environment Model which is used to predict the impacts of different management scenarios on lake activities.